The background description provided herein is for the purpose of generally presenting the context of the present invention. The subject matter discussed in the background of the invention section should not be assumed to be prior art merely as a result of its mention in the background of the invention section. Similarly, a problem mentioned in the background of the invention section or associated with the subject matter of the background of the invention section should not be assumed to have been previously recognized in the prior art. The subject matter in the background of the invention section merely represents different approaches, which in and of themselves may also be inventions. Work of the presently named inventors, to the extent it is described in the background of the invention section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present invention.
In existing wave wheel washing machines, the environment between inner and outer drums is closed, and only water can flow therein. Due to the limitation of the washing machine structure and the particularity of the user environment, dirt adheres to the outer wall of the inner drum and the inner wall of the outer drum after 3 to 5 months of use. Consequently, bacteria will breed in different extents, most of which are harmful to human body.
As people's living standards and the requirements of living quality increase, a solution to the sanitation of washing machines seems to be urgent. A survey conducted by a related scientific research institution on the internal environment of washing machines shows that consumers have started paying more and more attention to the severity of internal contamination of washing machines. To fundamentally prevent washing machines from bringing second-time dirt to the laundry and to be more responsible for users' health, the cleaning issue of the internal environment of washing machines needs to be addressed immediately.
Chinese Patent No. 200820183308.4 discloses a sleeve washing machine with walls between the drums cleaned. The washing machine includes an inner drum, an outer drum, and multiple circular silicone balls for cleaning the walls between the inner and outer drums. During washing, the inner drum rotates to drive the water to flow, thereby driving the silicone balls between the inner drum and outer drum of the washing machine to move and continuously collide with the walls between the inner and outer drums, so as to achieve the objective of cleaning the walls between the inner and outer drums.
By using the washing machine structure as described above, however, rubber balls or soft pellets are freely scattered in the drum after water drainage, which causes big noises during the high speed dewatering process, and also increases energy consumption and affects the service life of the washing machine.
In addition, Chinese Application No. 201010160548.4 discloses a washing machine using soft pellets to clean the environment between inner and outer drums of the washing machine and a method thereof. In the washing machine, soft pellets are placed between the inner and outer drums of the washing machine, and when laundry is washed, water flows regularly to drive the soft pellets to collide and rub the walls between the inner and outer drums of the washing machine, so as to clean the environment between the inner and outer drums of the washing machine.
By using the washing machine structure as described above, however, to strengthen the bottom of the inner drum, many reinforcing ribs are distributed at the bottom of the inner drum. The reinforcing ribs divide the external part of the bottom of the inner drum into multiple small grooves. The closer the grooves are to the center of the inner drum, the smaller the grooves are. Because the gap between the bottom of the inner drum and the bottom of the outer drum is small, it is difficult for water to flush between the bottoms of the inner and outer drums after long term use, and a lot of dirt is accumulated and hard to get rid of. Such bottom structure of the inner drum is not suitable for a washing machine with cleaning pellets for the following reasons: firstly, the reinforcing ribs at the bottom of the inner drum are high and the gap between the bottom of the inner drum and the bottom of the outer drum is small, thus it is not easy for cleaning pellets to enter the space between the bottoms of the inner and outer drums. Even though a few pellets could get in with the water flow, they are easily clamped or confined in the grooves and cannot get out, and the pellets between the inner and outer drums will be reduced in quantity, affecting the normal cleaning function of the drum walls. Secondly, because the reinforcing ribs are densely distributed and grooves are small, motions of the cleaning pellets that have entered the space between the bottoms of the inner and outer drums with the water flow fail to provide sufficient acceleration in the small grooves for the pellets to collide with the drum walls to clean the drum walls.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies.